Weed killers are getting ever more scrutiny, from Oregon's new water quality laws to studies about impacts on humans and plants.

The latest:

* The Wisconsin State Journal reported this weekend on the herbicide atrazine. Studies in Indiana and Washington indicate that gastroschisis, a birth defect in which the intestines grow outside the body, is more common among babies conceived in the spring when the levels of the herbicide atrazine in water are highest.

A study last year by doctors in Seattle showed a 60 percent higher incidence of gastroschisis among infants in Washington whose mothers lived within 15 miles of surface water tainted with atrazine, the article noted, compared to those living more than 30 miles away.

A spokeswoman for Syngenta, which makes atrazine, said more than 6,000 studies over 50 years, and the Environmental Protection Agency and World Health Organization, "have found atrazine to be safe at levels found in the environment."

* Roundup, the popular Monsanto herbicide used outside homes and in fields, faces concerns that it could cause infertility or cancer, Reuters reports.

The Environmental Protection Agency is examining the issue and has set a deadline of 2015 for determining if glyphosate should continue to be sold or in some way limited. The EPA is working closely with regulators in Canada as they also assess the ongoing safety and effectiveness of the herbicide.

Monsanto has said repeatedly that glyphosate is safe. The EPA also has discounted the validity of many of the studies cited in biomedical literature and by opponents, Reuters says. But it acknowledged there are areas that need more evaluation and has said it wants more data on human health risk and risks to certain endangered species.

Farmers and foresters have expressed alarm. Environmental regulators say they'll still let the state Department of Agriculture take the lead in enforcing water quality. Environmental groups say that could mean nothing gets done.

Today, 98 percent of U.S. soybeans, 88 percent or so of U.S. cotton and more than 70 percent of U.S. corn come from cultivars resistant to glyphosate, researchers said, creating the "perfect storm" for weed resistance.

Carol Mallory-Smith of Oregon State University studied the emergence of a noxious weed, jointed goatgrass. Its resistance to the herbicide imazamox is evolving in fields planted with wheat conventionally bred to be immune to imazamox.